Intracellular Localization Of HGF Receptor Fragments In Lung Fibroblasts

Taylor Buckner

School Name

South Carolina Governor's School for Science and Mathematics

Grade Level

12th Grade

Presentation Topic

Cell and Molecular Biology

Presentation Type

Mentored

Mentor

Mentor: Galina S. Bogatkevich, Department of Rheumatology and Immunology, Medical University of South Carolina

Abstract

Systemic sclerosis (SSc) is an irreversible fibrotic disorder with interstitial lung disease (ILD) being a major complication and leading cause of mortality. African American SSc patients exhibit higher prevalence of ILD and worse outcomes than those of other races. We previously reported that a cell-protective and antifibrotic factor, hepatocyte growth factor (HGF), is downregulated in bronchoalveolar lavage fluid and plasma from African American SSc-ILD patients compared with white SSc-ILD patients. It has also been reported that the HGF receptor, c-MET, can be cleaved by Caspase-3 and divided into 3 fragments: extracellular domain (100 kDa, designated as p100), kinase domain (40 kDa, designated as p40), and carboxy-terminal tail (1.1kDa, designated as M10). However, the role of these fragments inside of fibroblasts remains unknown. We hypothesize that intracellular localization of c-MET fragments depends on their specific functions within the cell. The purpose of this study is to observe the intracellular localization of the three protein fragments. Human lung fibroblasts were transfected with p100 and p40, cloned into pcDNA3.1 or treated with custom synthesized M10. Immunofluorescence study was performed using V5 antibody to detect p40 and p100 and C12 antibody to detect M10. We observed cytoplasmic and nuclear staining of p40 and M10 fragments. Our study indicates intracellular localization of HGF receptor fragments and suggests their role in the transmission of antifibrotic signaling to the nucleus.

Start Date

4-11-2015 11:00 AM

End Date

4-11-2015 11:15 AM

COinS
 
Apr 11th, 11:00 AM Apr 11th, 11:15 AM

Intracellular Localization Of HGF Receptor Fragments In Lung Fibroblasts

Systemic sclerosis (SSc) is an irreversible fibrotic disorder with interstitial lung disease (ILD) being a major complication and leading cause of mortality. African American SSc patients exhibit higher prevalence of ILD and worse outcomes than those of other races. We previously reported that a cell-protective and antifibrotic factor, hepatocyte growth factor (HGF), is downregulated in bronchoalveolar lavage fluid and plasma from African American SSc-ILD patients compared with white SSc-ILD patients. It has also been reported that the HGF receptor, c-MET, can be cleaved by Caspase-3 and divided into 3 fragments: extracellular domain (100 kDa, designated as p100), kinase domain (40 kDa, designated as p40), and carboxy-terminal tail (1.1kDa, designated as M10). However, the role of these fragments inside of fibroblasts remains unknown. We hypothesize that intracellular localization of c-MET fragments depends on their specific functions within the cell. The purpose of this study is to observe the intracellular localization of the three protein fragments. Human lung fibroblasts were transfected with p100 and p40, cloned into pcDNA3.1 or treated with custom synthesized M10. Immunofluorescence study was performed using V5 antibody to detect p40 and p100 and C12 antibody to detect M10. We observed cytoplasmic and nuclear staining of p40 and M10 fragments. Our study indicates intracellular localization of HGF receptor fragments and suggests their role in the transmission of antifibrotic signaling to the nucleus.